This invention generally relates to tools for installing nut-plate rivets, and more specifically relates to a nut-plate riveter which includes multiple pistons in a feed-through mandrel design.
Tools are used to install nut-plate rivets. It is advantageous to provide that such tools are lightweight, yet provide the required pulling force on a mandrel for installing a nut-plate rivet. It is also advantageous to provide that such tools are easy to assemble, use and maintain.
Many of the tools which are presently commercially available are pneumatic and provide that air pushes a piston in the tool in order to provide the required pulling force on a mandrel which pulls through the rivet. At least one of the tools which is available provides that a plurality of pistons are disposed in the tool, and the plurality of pistons assist (viz-a-viz the air supply) in providing the pulling force. By providing a plurality of pistons, less air pressure is needed to produce the requisite pulling force.
Although there is at least one tool presently available which includes multiple pistons, the tool is not configured such that a spent mandrel is automatically pulled through the tool (i.e., away from the nose of the tool). Providing that the spent mandrel is pulled through the tool is advantageous because, otherwise, the spent mandrel must drop out of the front of the tool, and this presents problems. Among other problems, such a design may lead to FOD (Foreign Object Debris) problems in the field, wherein contaminants enter the tool through the front end of the tool, causing the tool to jam, misfunction or break.